var rootHtml = "<div style='width: 570px; height: 350px;' id='tree'> ";
rootHtml += "<ul> <li><a>后台数据</a>";
	if(rootData != null || rootData != undefined ){
		rootHtml += "<ul>";
		for(var obj in rootData){
			rootHtml += "<li id="+obj.id+"><a>"+obj.name+"</a></li>";
		}
		rootHtml += "</ul>";
	}
rootHtml += "</li></ul></div>";

$("#leftmenu").html(rootHtml);